Slaughter is the final welfare challenge for farmed pigs — handling, lairage, stunning, and killing methods all significantly affect the welfare of billions of animals in their last hours of life.
The final hours of a pig's life in a slaughterhouse can involve significant welfare harms at each stage — mixing with unfamiliar pigs in lairage causes fighting and stress; handling toward the stun box involves fear and sometimes aversive driving; CO2 stunning causes a distressing period of consciousness before insensibility. The welfare costs of CO2 stunning are well documented and its continued dominance in industrial pig slaughter reflects economics and infrastructure rather than animal welfare considerations. Transitioning to less aversive stunning methods — LAPS or inert gas mixtures — is technically feasible and represents the most impactful single welfare improvement available in pig slaughter.